Dear FSL experts,
After inspection of our acquired DTI data, we found that for some participants the B0-volume was the first volume, whereas for all the other participants the B0-volume was the last. We initially thought this was due to the conversion from PAR/REC to nifti, but different conversion programs yielded similar results. This was odd since all participants were scanned using the same protocol.
This raised some questions:
1.) Can we move the B0-volume, in order for all participants to have their B0-volume as their last volume (i.e., does TBSS require this internal consistency)? If so, how do we do this in FSL and is this a valid action?
2a.) If we were to move the B0-volume, do we have to edit the bvecs files as well, in order for both files to match?
2b.) Could it be the case that flipping the B0-volume caused the entire series to flip (i.e., reverse acquisition compared to participants whose B0-volume is the last volume)?
3.) How do we distinguish the trace image from the diffusion volumes and could it be so that this image is not acquired?
Thank you in advance.
Kind regards,
Jurjen Heij
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